An Australian international and New South Wales State of Origin representative fullback, he played his entire NRL career for the Sea Eagles, with whom he won the 2008 and 2011 Premierships.After playing from the bench in a 30–22 loss to the Wests Tigers at Leichhardt Oval in Round 7 of the 2004 NRL season, rookie coach and dual Manly premiership player Des Hasler moved former dual international Andrew Walker from fullback to five-eighth to bring Stewart in as the Sea Eagles fullback in Round 9 against the St. George Illawarra Dragons at Brookvale Oval.He made his State of Origin debut in Game 2 of the 2007 series, replacing injured Anthony Minichiello at late notice, and scored a try.While Stewart did not cross for a try in the GF, he provided the last pass on a couple of occasions for teammates to score, including the last try of the game for departing Centre, Steven Bell.In the lead-up to the WCC, Manly became the first Australian side travelling to England to actually play a warm-up game, defeating the Harlequins RL at The Stoop in London, winning 34–26.Stewart featured in the NRL's 2009 television advertising campaign, alongside Storm player Greg Inglis as the "faces of rugby league".[17] Following his injury forced retirement from playing in 2016 (though he was still a contracted Manly player in 2017), Stewart divides his time between his home in Sydney and the Toko Japanese restaurant (of which he is a 1/3 part owner) in Melbourne.At the opening and closing of his trial, jurors were told by the judge that Stewart deserves the presumption of innocence despite the high number of sexual assault cases involving high-profile players that have received media attention in Australia in recent years.[34] On 16 June 2012 The Sydney Morning Herald and Age newspapers published a lengthy investigation by journalist Mark Whittaker asserting that the father of the alleged victim had a long history of fraud.